when washer drains, water backs up into shower

I have a shower downstairs next to my laundry room. When the washing machine drains the water backs up into the shower through its drain. After the washing machine stops draining, the water in the shower drains out pretty quickly. The toilet in the bathroom (with the shower) flushes fine and does not cause any backup into the shower.

Do I have a partial clog somewhere near the shower drain or could this be caused by a venting problem, or anything else?

My best guess is that you need to have your sewer cleaned. A washing machine expels probably the greatest amount of water in the shortest time of anything in your house. If you have a partial obstruction in the sewer, you will certainly see a backup when the machine empties. Flushing the toilet only puts several gallons of water into the sewer. If this just started happening, I would say the sewer is backing up. If you have always had this problem, the drain may be constructed in such a way that it cannot handle a large volume of water at that point of entry.

I'm having a similar problem just recently, but am on a septic system. Also, water goes down in both toilets in the house when the shower is backing up and both gurgle with air bubbles popping up. House is only 9 months old. Suggestions?

Milfax... are you in an area where there are inspectors and permits required for building trades such as plumbing? It sounds like you do not have adequate venting or a vent is blocked. Sounds like rihokie has a similar problem unless it is just poorly designed drain system. If the shower and washing machine are both on the same 2" line then that could be the problem especially if they are very close together. If they are on separate branches and there were no blockages then there should be no problem.

Your septic is full or the piping is getting plugged. The gurgling occurs when the sewer has filled the system and there is still air between the toilet's trap and the water, but the vent has been submerged so the air cannot exit that way.

Thanks for the help all, but we found the culprit. Turns out that starting with my house, the builders installed some sort of honeycomb-like filter between the septic and the pump to the leech field. So, in a round about way, the septic was full since it wasnt clearing. Again, thanks for the help and I'll keep in mind the front loading washer idea for next time I buy one.
Troy

Is that a filter to keep the solids out of the field lines? I know those filters are required in this area and are supposed to protect the field lines from filling up with solids... just wondering if I have that to look forward to in the future.

Last night water from my washer gurggled and bubbled into the toilet which is located about 10 feet away from the laundry room. It was a small load thank goodness. When the water emptied again for the rinse cycle, the water gurgled loudly again. by the time I got to the bath from the next room the water was overflowing.
The only other problem I have is that my shower upstairs has a gassy smell most days. I am not sure it is sewer gas, but definitely smell coming up from the drain.
My townhouse is on a slab and I am scared about what may need to be done.

JWJ as stated there is a either drainage or venting problem, (either do to a plugged drain or pipe or it was not sized correctly or some thing else has happened that is causing restriction in the drainage system).

if it was working correctly for a long period of time before this and no bubbling or gurgling sounds, then the chances of it being a blockage are great, sounds like to me it time to call some one who does drain cleaning in and get the restriction or blockage fixed,

if the shower is not used often it could be that the water in the trap has evaporated, if it is use then my guess is there is an incorrect piping in the venting system or a lack of a vent system for the shower. and or it could even be connected to the (potential blocked drain before talked about)

if you have a pipe and you dump water in it and the one end is blocked, air will be trapped in the pipe, by water at one end and the blockage at the other, it has to go some where, and depending on if the venting was done correctly or not, it is either going to escape up the vent pipe, but if there no vent pipe or it is plugged, then it may find a drain and pass back up through the trap, bubbling and gurgling, and many times with smell.

Thanks
The townhouse was built in 2002. I moved in October 1st last year. I do not know if problems had been there before.
The shower is used at least 4 days per week. I travel some and it is not used then. Then tub in that bath, and the tub and toilet in the other upstairs bath are not used frequently.
I think the sewer drain must be blocked. I have called the city to check their side of the problem, and will call a sewer and drain specialist to look at mine. Any other tips?

Thanks
The townhouse was built in 2002. I moved in October 1st last year. I do not know if problems had been there before.
The shower is used at least 4 days per week. I travel some and it is not used then. Then tub in that bath, and the tub and toilet in the other upstairs bath are not used frequently.
I think the sewer drain must be blocked. I have called the city to check their side of the problem, and will call a sewer and drain specialist to look at mine. Any other tips?

I want to move the washer and Dryer out to the garage. The wall behind the Bathtub fixtures is where I want to put them.

I can connect to the Hot and Cold water there, but I am not sure about the drain. Can it handle the amount of water that the washer will put out? Is the tub drain large enough to handle the Wash Machine Drain?

I want to move the washer and Dryer out to the garage. The wall behind the Bathtub fixtures is where I want to put them.

I can connect to the Hot and Cold water there, but I am not sure about the drain. Can it handle the amount of water that the washer will put out? Is the tub drain large enough to handle the Wash Machine Drain?

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Starting a new thread is more helpful than not.

You need to think of the local codes when moving any fixture.
The drain might be big enough for a few fixtures but do your local codes allow your washer to be connected to those other fixtures.

Many people including plumbers tend to get confused over this issue. If the problem only occurs when your laundry is discharging it is a venting issue. The culprit involved in this issue is your laundry detergent. When your laundry drains all the soap bubbles up and chokes your line not allowing it to vent properly. Without enlarging your vent line and/or AAV (air admittance valve) the easiest fix is to use HE (high efficency) laundry detergent. This is generally used in a commercial enviroment and does not suds up the way normal detergents do.